Protect a PDF with a password
Lock your PDF with strong AES-256 encryption so only people with the password can open it, and control printing, copying and editing.
- Processed on your device, never uploaded
- Free, no sign-up, no watermark
Done
This PDF is protected. Enter its password to open it.
About Protect PDF
This tool locks a PDF with a password using AES-256 encryption (PDF 2.0 "AESv3"). You can also choose whether people can print, copy text and images, fill forms and comment, or edit and rearrange pages. It is a free way to password protect a PDF online, with no sign-up and no watermark.
You type the password twice, set the permissions, and download the protected file. An advanced option lets you set a separate permissions password for changing permissions later. If you leave it empty, a random one is made for you.
It suits anyone sending private documents. For example, an accountant can password protect a client's tax return PDF before emailing it, and turn off editing so the figures can't be changed. Encryption happens in your browser, and neither the PDF nor the password is uploaded. A forgotten password cannot be recovered, so keep it somewhere safe.
How to use Protect PDF
- Drop your PDF on the page, or click Choose file.
- Enter a password, then repeat it.
- Choose permissions: Print, Copy text and images, Fill forms and comment, and Edit and rearrange pages.
- Optional: set a permissions password in the advanced settings.
- Click Protect PDF, download the file and keep the password safe.
AES-256 encryption
The strongest standard PDF encryption (PDF 2.0, AESv3), supported by Adobe Reader, browsers and phones.
Permissions
Choose whether people can print, copy text, fill forms or edit.
Private by design
Encryption happens in your browser. Your PDF and password never leave your device.
Free, no limits
No sign-up and no watermark.
Example
Input: tax-return-2025.pdf.
You set a long password and leave only Print turned on.
You click Protect PDF.
Result: an encrypted PDF that asks for the password and can't be edited.
Protect PDF: questions people ask
How strong is the protection?
It uses AES-256 (PDF 2.0 "AESv3"). A long, unusual password matters most.
What if I forget the password?
It can't be recovered by Omebly or anyone else. Keep a copy of the original PDF or store the password in a password manager.
Do all apps respect the permissions?
Mainstream PDF readers and browsers do, but some apps ignore them. The open password can't be bypassed.
Is my password sent anywhere?
No. Neither the file nor the password leaves your browser.
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